PHOSPHURETTED HYDROGEN. 219 



PHOSPHURETTED HYDROGEN". 

 544. DESCRIPTION. Phosphuretted hy- 



Whatisphos- . r J 



pkurettedky- drogen is a colorless gas, of an odor that 



drogen? hag been compare( i to t h at Q f p utr id fish. 



It is spontaneously inflammable by contact with the 

 air. In the relative proportion of its elements, it cor- 

 responds with ammonia. This gas is sometimes pro- 

 duced in the decay of vegetable and animal matters. 

 The jack-o-lantern, or will-o-t he-wisp, sometimes seen 

 in swamps and grave-yards, is supposed to have its 

 origin in the spontaneous production and combustion 

 of this gas. 



How is it pre- 545. PREPARATION. Phosphuretted hy- 

 pared? drogen is made from phosphorus, with the 



help of water and an alkali. Water furnishes the requi- 

 site hydrogen, if lime or potash is at the same time 

 present. Introduce into a small vial two-thirds full of 

 water, a stick of ordinary fused potash, broken in pieces, 

 and a bit of phosphorus of the size of a pea. On the 

 application of heat, this gas is evolved. It is carried 

 through a pipe-stem, and al- 

 lowed to bubble up through 

 water contained in a tea-cup 

 or bowl, as represented in the 

 figure. If the atmosphere is 

 still, the bubbles, as they burst 

 and inflame, form beautiful 

 white rings, which rise in succession into the air. 

 These rings consist of particles of phosphoric acid, 

 produced by the combustion of the phosphorus which 



